Why routing organizes endpoints in FastAPI - See It in Action

Why routing organizes endpoints

📖 Scenario: You are building a simple web API for a bookstore. You want to organize your code so that different parts of the API handle different tasks clearly and neatly.

🎯 Goal: Build a FastAPI app that uses routing to organize endpoints for books and authors separately.

📋 What You'll Learn

Create a FastAPI app instance called app

Create two routers: books_router and authors_router

Add one GET endpoint to books_router at path /books/ that returns a list of book titles

Add one GET endpoint to authors_router at path /authors/ that returns a list of author names

Include both routers in the main app with prefixes /books and /authors respectively

💡 Why This Matters

🌍 Real World

Web APIs often have many endpoints. Routing helps keep code organized and scalable.

💼 Career

Understanding routing is essential for backend developers building APIs with FastAPI or similar frameworks.

1

Create the FastAPI app and routers

Import FastAPI and APIRouter from fastapi. Create a FastAPI app instance called app. Create two routers called books_router and authors_router using APIRouter().

FastAPI

from fastapi import FastAPI, APIRouter

# Create the FastAPI app instance

# Create the books_router

# Create the authors_router

Need a hint?

Use app = FastAPI() to create the app. Use APIRouter() to create routers.

2

Add GET endpoint to books_router

Add a GET endpoint to books_router at path /books/ that returns a list of book titles: ["The Hobbit", "1984", "Pride and Prejudice"]. Use the decorator @books_router.get("/") and define a function called get_books.

FastAPI

from fastapi import FastAPI, APIRouter

app = FastAPI()

books_router = APIRouter()
authors_router = APIRouter()

# Add GET endpoint to books_router

Need a hint?

Use @books_router.get("/") to create the endpoint. Return the exact list of book titles.

3

Add GET endpoint to authors_router

Add a GET endpoint to authors_router at path /authors/ that returns a list of author names: ["J.R.R. Tolkien", "George Orwell", "Jane Austen"]. Use the decorator @authors_router.get("/") and define a function called get_authors.

FastAPI

from fastapi import FastAPI, APIRouter

app = FastAPI()

books_router = APIRouter()
authors_router = APIRouter()

@books_router.get("/")
async def get_books():
    return ["The Hobbit", "1984", "Pride and Prejudice"]

# Add GET endpoint to authors_router

Need a hint?

Use @authors_router.get("/") to create the endpoint. Return the exact list of author names.

4

Include routers in the main app with prefixes

Include books_router in app with prefix /books. Include authors_router in app with prefix /authors. Use app.include_router() for both.

FastAPI

from fastapi import FastAPI, APIRouter

app = FastAPI()

books_router = APIRouter()
authors_router = APIRouter()

@books_router.get("/")
async def get_books():
    return ["The Hobbit", "1984", "Pride and Prejudice"]

@authors_router.get("/")
async def get_authors():
    return ["J.R.R. Tolkien", "George Orwell", "Jane Austen"]

# Include routers in app with prefixes

Need a hint?

Use app.include_router() with the correct router and prefix.